A Consolidated Pulp Test System Including Flowmetry, Pulse Oximetry, and Thermometry.

AIM: The aim of this study is to report manufacturing a consolidated pulp test system that includes thermometry, flowmetry, and pulse oximetry. BACKGROUND: The ideal method for the evaluation of pulp vitality should be objective, noninvasive, easy to use, reliable, and painless. Currently, the most commonly used tests (such as electricity, heat, and cold tests) depend on patients' sensibility and are highly subjective. They only measure a neural response and do not indicate the actual biologic status of the pulp. It has, therefore, been suggested that vitality tests such as flowmetry, pulse oximetry, thermometry, and photoplethysmography be used. Some research has been done on these systems; however, their high costs and space need to maintain all of them that have been obstacles to their use. TECHNIQUE: This report describes designing and manufacturing a novel system for evaluating pulp vitality involving the use of three methods (flowmetry, pulse oximetry, and thermometry) combined in a single small system using only two probes. CONCLUSION: The consolidated pulp tests system may be accurate in determining the pulp vitality. However, after clinical use, some changes may be necessary for improvement of the system.

Smear Layer Removing Ability of Root Canal Irrigation Solutions: A Review.

AIM: The purpose of this review is to address the smear layer removing the ability of root different canal irrigants including ethylenediaminetetraacetic acid (EDTA), a mixture of tetracycline, acid and detergent (MTAD), tetraclean, citric acid, Q-Mix, maleic acid, and smear clear. BACKGROUND: Smear layer is a layer which is produced during instrumentation. It contains both organic and inorganic materials. It may also contain bacteria and their byproduct considering the root canal situation. This layer may prevent the penetration of the healing material introduced to the canal to the interior of the dentinal tubules. In addition, it can affect the adaptation of sealing materials to the root canal walls. REVIEW RESULTS: The smear layer removal ability of MTAD is superior and faster than EDTA. Tetraclean is similarly composed of an acid, an antibiotic, and a detergent. The presence of doxycycline is believed to help the smear layer removal ability of these irrigants. Antibiotics such as tetracycline had similar smear layer removal ability as even citric acid. EDTA is an amino acid with a chelating ability that sequestrates metal ions. Some believed EDTA smear layer removing ability is better than MTAD, tetraclean, SmearClear, and 20% citric acid which is controversial in case of comparison between MTAD and EDTA. Phosphoric acid is efficient enough to be comparable to EDTA in removing the smear layer. Maleic acid is an organic compound with acid etching smear layer removal. Its ability seems to be similar or even better than EDTA. Citric acid as another organic acid is believed to be used as smear removing agent. HEBP is another chelating agent that can be used in combination with NaOCl; however, HEBP is a weak decalcifying agent compared to EDTA and hence cannot be applied as a mere final rinse. QMiX is a combination of CHX, EDTA, and detergent and should be used at final rinse. It is believed that QMiX is as efficient as EDTA. Smear clear is a 17% EDTA solution including an anionic and cationic (cetrimide) surfactant. The ability of QMiX is similar to EDTA. CONCLUSION: There are different canal irrigation solutions with various smear layer removal ability that some should be used as a mere final rinse and some should not. CLINICAL SIGNIFICANCE: The usage of canal irrigation solutions depends on the clinical situation and preference of the dentists. This study provides a good guide for clinician of the field.

A Review on Triple Antibiotic Paste as a Suitable Material Used in Regenerative Endodontics.

As the root canal system shows different and complicated anatomies, mechanical instrumentation alone has not the ability to provide a bacteria-free environment in root canals. On the other aspect, necrotic tissue remaining can decrease the effects of root canal irrigants and medicaments and also interfere with the adaptation of root canal fillings to dentin. As a result, certain disinfection and irrigation procedures are required to remove the remaining tissues from the root canal area thoroughly and also be able to eliminate the microorganisms. Triple antibiotic paste (TAP) containing metronidazole, ciprofloxacin and minocycline has been proposed as a root canal medicament due to its antimicrobial effects in endodontic regenerative procedures. The purposes of this review were to determine the properties of TAP drugs and to evaluate the efficiency of TAP on the root canal disinfection, in primary and permanent teeth, along with its affection in regeneration/revascularization procedures. The biocompatibility and disadvantages of this medicament were also discussed.

Prevalence and Reasons for Extraction of Endodontically Treated Teeth in Adult Nigerians.

AIM: Teeth extraction is an important problem in elder patients. Although some of these teeth have been endodontically treated, many of them may be subjected to extraction. The reasons for extraction are important for prevention planning in further patients. The aim of this study was to assess the prevalence and important reasons for extraction of endodontically treated teeth in adult Nigerians. MATERIALS AND METHODS: This study involved a retrospective examination of 2,000 case files in the archives of the University of Nigeria Teaching Hospital. Out of the 2,000 case files, 650 concerned endodontically treated teeth. RESULTS: The prevalence of extractions in the population was 21.5%. This was more often in the mandible (67.9%) than in the maxilla (32.1%). In both jaws, more molars were extracted (57.1%), followed by premolars (27.1%) and anterior teeth (15.7%). Extractions occurred 57.1% of times in females. However, the rate of extraction decreased with age but peaked in the 51-60 year age band. CONCLUSION: The association between age and extraction was proven. Caries, vertical root fracture and endodontic reasons accounted for the commonest cause of extraction in the mandible; while in the maxilla, endodontic reasons and cusp fracture caused extractions most often. CLINICAL SIGNIFICANCE: The reasons for extraction of endodontically treated teeth are different between maxilla and mandible.

Photodvnamic Therapy in Endodontics.

Commonly used irrigants do not always eradicate the entire microbial flora in infected root canals. Therefore, several other strategies, such as photodynamic therapy (PDT) have been developed. Photoactivated disinfection is based on the interaction of a photosensitive antibacterial agent and a light source. It uses a nontoxic dye named photosensitizer (PS) and low-intensity visible light. In oxygen presentation, these combine to produce some cytotoxic species. The PS molecules attach to bacteria membrane. Irradiation with a specific wavelength of the light may lead to the production of singlet oxygen, resulting in rupture of the microbial cell wall. There are several applications for PDT in dentistry. A successful periodontal treatment is based on elimination of bacteria from the infected area. Phenothiazinium PSs have been shown to be highly effective and safe for this purpose. However, scaling/root planing should be performed before the PDT. While performing the PDT, PS should be first injected in the periodontal pocket and allowed to pigment. Then, the special fiber should be inserted 1 mm short of the pocket base and lased. Photodynamic therapy has also been used to disinfect caries dentin before restoration, disinfecting oral tissues before or during surgical procedures, treating denture stomatitis, and treating oral candidiasis in immunocompromised patients. Photodynamic therapy can be used in combination with mechanical instrumentation and chemical antimicrobial agents, such as sodium hypochlo-rite, too. The purpose of this study was to review historical perspective, mechanism of action, and applications of PDT in dentistry and especially in endodontics was reviewed. Furthermore, the effects of PDT on dentin bonding and endo-toxin are discussed. CLINICAL SIGNIFICANCE: Photodynamic therapy has been advocated to increase the disinfection level of the root canal system.

Unusual Root Canal Irrigation Solutions.

Microorganisms and their by-products play a critical role in pulp and periradicular pathosis. Therefore, one of the main purposes of root canal treatment is disinfection of the entire system of the canal. This aim may be obtained using mechanical preparation, chemical irrigation, and temporary medication of the canal. For this purpose, various irrigation solutions have been advocated. Common root canal irrigants, such as sodium hypochlorite, chlorhexidine, and a mixture of tetracycline, acid, and detergent have been extensively reviewed. The aim of this review was to address the less common newer root canal irrigation solutions, such as citric acid, maleic acid, electrochemically activated water, green tea, ozonated water, and SmearClear.

Additive and reducing Effects between Calcium Hydroxide and Current Irrigation Solutions.

INTRODUCTION: Microorganisms should be considered to have the major role in starting and perpetuation of pulpo-periapical diseases. Using intracanal medicaments is necessary to gain a bacteria-free environment in the canal system. Calcium hydroxide (abbreviated as Ca(OH)2), which is the most commonly used medicament in endodontic therapy, has been shown to be effective against primary sources of infection; however, its effectiveness against some microorganisms, such as Candida albicans and Enterococcus faecalis has not been proved. On the other hand, sodium hypochlorite (NaOCl), chlorhexidine (CHX), and iodine potassium iodide (IKI) have been shown to be the potent medicaments against these microorganisms. Because of this fact, combination of Ca(OH)2 and some irrigants of the root canal has been suggested as potential intracanal medicaments. The aim of this literature review is to identify and address the efficacy of Ca(OH)2 in combined with some of these irrigating solutions.

Establishing Apical Patency: To be or not to be?

INTRODUCTION: The apical portion of the root canal is very complex and challenging during endodontic treatment. Root canal preparation and obturation to the apical constriction may provide the best prognosis. Incomplete debridement, foramen transportation, and inadequate seal in the apical portion are considered to be responsible for treatment failure. The technique "apical patency" is considered as a way for maintaining the apical part the free of the debris by recapitulation, using a small K-file through the area of the apical foramen. This term was firstly proposed by Buchanan. In this technique, the smallest diameter file is set 1 mm longer than working length and recapitulated after each instrument to prevent packing of debris in the apical part. Apical patency has been found to be effective in achieving an apical seal with gutta-percha. Teeth prepared with a step back method and with maintained apical patency may show less leakage when obturated with cold lateral condensation technique. Data regarding the effect of apical patency on the healing of periapical tissue are very scarce, and it has been shown that the patency file has detrimental effect on the healing of periapical tissues in animal studies. However, using patency file in endodontic treatment is controversial and further studies are needed. The purpose of this article is to review the effect of using a patency file on the extrusion of root canal contents, the apical seal, postoperative pain, and healing of periapical tissues. Furthermore, the effect of establishing patency on reaching irrigation solutions to the apical portion of the canal and prognosis of root canal treatment are discussed. CLINICAL SIGNIFICANCE: Keywords: Apical patency, Apical seal, Apical transportation, Postoperative pain, Prognosis.

Lasers in Apicoectomy: A Brief Review.

Since the invention of laser, various applications for lasers in endodontics have been proposed, such as disinfection of the root canal system, canal shaping, pulp diagnosis, and apico-ectomy. One of the major applications of laser in endodontics is apicoectomy. The aim of this article is to review the benefits and drawbacks of laser applications in apicoectomy, including effect on apical seal, effect on dentin permeability, effect on postsurgery pain, effect on crack formation, effect on root-end morphology, effect on treatment outcome, and connective tissue response to laser-treated dentin.

Laser-based Disinfection of the Root Canal System: An Update.

INTRODUCTION: Microorganisms have been considered to have played a critical role in the initiation and development of pulpo-periapical diseases. Some evidences have shown that mechanical instrumentation may leave considerable portions of canal surfaces undebrided. Therefore, some supplemental methods, such as the use of chemical solutions and/or lasers, have been introduced to further disinfect the complicated canal anatomy and destroy as many microorganisms as possible. The purpose of this review was to address a brief review of characteristics of lasers and their effects to disinfect the root canal in endodontics.

Human Pulp Response to Direct Pulp Capping and Miniature Pulpotomy with MTA after Application of Topical Dexamethasone: A Randomized Clinical Trial.

INTRODUCTION: The aim of this randomized clinical trial was to compare the histologic pulp tissue response to one-step direct pulp capping (DPC) and miniature pulpotomy (MP) with mineral trioxide aggregate (MTA) after application of dexamethasone in healthy human premolars. METHODS AND MATERIALS: Forty intact premolars from 10 orthodontic patients, were randomly chosen for DPC (n=20) or MP (n=20). In 10 teeth from each group, after exposure of the buccal pulp horn, topical dexamethasone was applied over the pulp. In all teeth the exposed/miniaturely resected pulp tissue was covered with MTA and cavities were restored with glass ionomer. Teeth vitality was evaluated during the next 7, 21, 42, and 60 days. Signs and/or symptoms of irreversible pulpitis or pulp necrosis were considered as failure. According to the orthodontic schedule, after 60 days the teeth were extracted and submitted for histological examination. The Kruskal-Wallis and Fisher's exact tests were used for statistical analysis of the data (P=0.05). RESULTS: Although dexamethasone specimens showed less inflammation, calcified bridge, pulpal blood vasculature, collagen fibers and granulation tissue formation were not significantly different between the groups (P>0.05). CONCLUSION: Topical dexamethasone did not hindered pulp healing but reduced the amount of underlying pulpal tissue inflammation after DPC and MP in healthy human premolars.

Resilon: Review of a New Material for Obturation of the Canal.

Resilon is a thermoplastic synthetic polymer-based endodontic material alternative to gutta-percha. It contains bioactive glass and also radiopaque fillers. It has the same handling properties as gutta-percha. For endodontic retreatment, it may be dissolved with some solvents, such as chloroform or softened with heat. The composition of Resilon and its sealer (Epiphany) bond to dentin and form a monoblock. A review of the literature and a discussion of its properties comparing to other root canal filling materials are presented.

Effects of KTP Laser Bleaching on Traumatized Tooth Enamel.

BACKGROUND: Bleaching of traumatized discolored teeth is considered an important issue in esthetic dentistry. Various methods have been introduced for bleaching, some of which may have adverse effects on soft or hard tissues of the tooth. OBJECTIVES: The objective of the study was to evaluate the effects of KTP laser bleaching on enamel of traumatized teeth. MATERIALS AND METHODS: A square of 36 mm(2) was chosen on the labial surface of 32 extracted teeth. The corners were drilled in order to indicate the location precisely. The shade of each sample was recorded and the teeth were divided into four groups, each with eight teeth: group A (Smartbleach with KTP laser for 30 seconds), group B (Smartbleach with G-Light for 5 minutes), group C (only Smartbleach for 10 minutes) and group D (control group with no bleaching). After one session of bleaching, shade assessment was performed again. In another experiment on nine teeth, Smartbleach with KTP laser was used for 150 seconds to 1500 seconds. The samples were critically processed and observed by using scanning electron microscope (SEM) to assess enamel damage. Data was statistically analyzed using Kruskal-Wallis test (confidence interval level were set at 95%). RESULTS: Smartbleach was highly effective when used with KTP laser (P = 0.0419). Enamel damage was observed after frequent KTP bleaching and 750 seconds of KTP bleaching was recognized as the limit by morphological evaluation via SEM, indicating a major difference between under and over 750 seconds of bleaching. CONCLUSIONS: Application of KTP laser may increase the bleaching effect of Smartbleach, nevertheless it may cause some enamel damage.

Vital Bleaching of Tetracycline-Stained Teeth by Using KTP Laser: A Case Report.

Bleaching of discolored teeth is one of the most important topics in aesthetic dentistry. A great challenge in this area is obtaining good results in tetracycline-stained teeth. The wavelength and features of KTP laser, which is a type of Nd:YAG laser, seem to be appropriate for bleaching of these teeth. This case report underlines the importance of knowledge about the photochemical bleaching by using the KTP laser and its side effects on soft tissues.

Basic study of the use of laser on detection of vertical root fracture.

OBJECTIVE: Many methods are used to detect vertical root fractures, but most are not adequate for identification of incomplete fractures or cracks. The purpose of this study was to evaluate the effects of three detergents on detection of vertical root fractures by DIAGNOdent with methylene blue (MB) solution. METHODS: Vertical incomplete fractures were artificially created on the roots of extracted human teeth, the DIAGNOdent values (D values) recorded in the presence or absence of MB solution, and the effects of detergents on D values examined. The effects of 20% ethanol on enhancing detergent action were also investigated. Statistical analysis was performed using the Mann-Whitney U-test; a value of p<0.01 was considered significant. RESULTS: D values increased significantly when MB solution was used with 0.1% or 1.0% polyoxyethylene (10) octylphenyl ether compared to MB solution only. CONCLUSION: These findings suggest that 0.1% or 1.0% polyoxyethylene (10) octylphenyl ether could be used as an enhancer for detection of vertical root fractures by DIAGNOdent using MB solution.

The application of tooth temperature measurement in endodontic diagnosis: a review.

Teeth with vital pulp are those with an adequate vascular supply, so the circulatory status, and not sensitivity response of the pulp tissue, has been proposed to assess pulp vitality. Some experimental methods have been used to assess this; one of them is the measurement of tooth temperature, which may indicate the pulp vasculature. Some authors have found no differences between the temperatures of teeth with vital and nonvital pulp; however, others found that teeth with nonvital pulp have lower temperatures than teeth with vital pulp. Temperature measurement as a diagnostic procedure has been described with the use of thermocouple, thermistors, infrared thermography, and cholesteric liquid crystals. Many factors may influence the results of the temperature measurement procedure. For creating controlled conditions, each patient should be examined in a thermologic environment. Patients should be asked to refrain from smoking and eating/drinking for 60 minutes before the procedure. The room should be insulated and draft free, and the temperature should be maintained at 20 degrees C. It is desirable to have them lie down or sit with adequate support for the head. The use of a rubber dam is also advocated. Tooth temperature measurement as a diagnostic procedure is reviewed to include description of devices for the test, associated factors, and value of the test.

Light intensity evaluation of laser-induced fluorescence after caries removal using an experimental caries staining agent.

OBJECTIVE: The purpose of this study was to evaluate the intensity of fluorescent light reflected from cavity wall dentin, after dentin stained by an experimental caries detecting liquid was removed. BACKGROUND DATA: The conventional caries detecting liquid tends to penetrate dentin too deeply. On the other hand, DIAGNOdent has gradually gained recognition and established itself as a caries detection device using a laser beam. METHOD: An experimental caries staining liquid or the conventional caries staining liquid was applied in the same cavity to observe for differences in dye penetration. Intensity of fluorescence reflected from treated dentin was measured by DIAGNOdent. RESULTS: The mean DIAGNOdent value after removing the tooth substance stained by the experimental liquid was 17.9+/-4.1, compared with 7.7+/-2.7 by conventional one. CONCLUSION: Light intensity evaluation of laser-induced fluorescence suggested that the experimental caries detecting liquid did not penetrate the dentin which should be preserved, hence avoiding overtreatment.

Effects of KTP laser irradiation, diode laser, and LED on tooth bleaching: a comparative study.

OBJECTIVE: This in vitro study examines the whitening efficacy of a light-emitting diode (LED), a diode laser, and a KTP laser irradiation in dental bleaching by analyzing the change in color achieved from the treatment, the temperature increase induced in the pulpal cavity, as well as enamel microhardness measurement after treatment. BACKGROUND DATA: Bleaching techniques achieved significant advances with the use of coherent or incoherent radiation sources to activate the bleaching agents. METHODS: A hydrogen peroxide bleaching agent, Hi-Lite, was stimulated with an LED, a 980-nm diode laser at 0.8 W, or a 532-nm KTP laser at 1.0 W for 30 sec on 64 extracted human incisors. During irradiation, the temperature in the pulpal cavity was monitored. The color change was evaluated using the CIE L*a*b* color space measurement system, and Vikers enamel microhardness was tested after treatment. RESULTS: A mean total color difference value (DeltaE*) greater than 5.0 was obtained in each group. KTP-laser-induced bleaching gave a significantly higher DeltaL* (8.35) after treatment (p < 0.01). Neither LED nor the two lasers produced significant differences in the enamel microhardness after treatment (p > 0.01). Mean maximal pulpal temperature rise was 2.95 degrees C for LED, 3.76 degrees C for KTP laser, and 7.72 degrees C for diode laser, respectively. CONCLUSION: The results of this study suggest that KTP laser is effective at providing brighter teeth. According to the conditions used in this study, the LED and KTP laser induced a safer pulpal temperature increase when assisted with Hi-Lite bleaching gel.

Effect of a novel Er:YAG laser in caries removal and cavity preparation: a clinical observation.

OBJECTIVE: We evaluated the applicability of a novel Er:YAG laser under clinical conditions. BACKGROUND DATA: The Er:YAG laser has been demonstrated to be a safe and effective alternative to the conventional turbine bur, but the relatively low cutting speed prevented the wide application of Er:YAG laser in clinical cavity preparation. METHODS: A Smart 2940 D laser developed by Deka Corporation was used for cavity preparation in 95 teeth of 45 patients. Parameters were as follows: wavelength 2.94 microm, pulse energy 700 mJ, repetition rate 8 Hz. Pain, discomfort, assessment during cavity preparation, prognosis factor, and overall clinical evaluation were assessed during or after treatment. RESULTS: No adverse reaction was observed in any tooth. No intraoperative pain or only slight intraoperative pain was described in 85 teeth (89.5%). Cavity preparation was completed with the laser system alone in 90 teeth (94.7%). Overall clinical evaluation showed no safety problems, with a very good or good rating in 86 teeth (90.5%). The overall operation time was 49 sec on average. CONCLUSION: The Smart 2940 D is an efficient, effective, safe, and suitable instrument for caries removal and for cavity preparation. It greatly shortens operation time.

An assessment following root canal preparation by Er,Cr: YSGG laser irradiation in straight and curved roots, in vitro.

In the present study, the effectiveness of Er,Cr:YSGG laser in straight and curved root canal preparation was compared with that of the conventional canal preparation technique, in vitro. The degree of root curvature of 40 root canals was determined, and then 20 canals were prepared by an Er,Cr:YSGG laser of 2 W by using the crown-down technique, while the other 20 canals were shaped by K-file (control). The achievement degree of root canal preparation and debris score was investigated morphologically. The results indicated that straight root canals could be successfully prepared by Er,Cr:YSGG laser irradiation; a significant decrease of smear layer or debris was also recognized (P<0.01). However, canal preparation by laser device in curve root often leads to a ledge or zipped formation, perforation or over-instrumentation. The results demonstrated that further development in laser device and technique are required to ensure its success in root canal preparation, especially in curve root.